Soft polyolefin compositions and highly filled compounds thereof

ABSTRACT

Flexible polyolefin compositions with improved balance of properties particularly for applications where softness and ductility at low temperature is requested comprising:
         A) from 20 to 40% by weight of a crystalline polymer fraction consisting of a propylene homopolymer, or a copolymer of propylene, or mixtures thereof, said crystalline fraction having a xylene insoluble fraction at 25° C. of at least 90% by weight.   B) from 60 to 80% by weight of an elastomeric fraction consisting of a copolymer or blend of copolymers of propylene with one or more alpha-olefins, and optionally with minor quantities of a diene; said copolymer or blend containing ethylene in a quantity lower than 40% by weight.
 
the fraction soluble in xylene at 25° C. of said polyolefin composition having IVgpc lower than 2.5 dl/g, Mw/Mn (GPC) equal to or higher than 4, Mz/Mw (GPC) equal to or higher than 2.5
 
Said polyolefin composition optionally further comprising an inorganic filler (II) selected from flame-retardant inorganic fillers and inorganic oxides or salts.

FIELD OF THE INVENTION

The present invention concerns soft polyolefin compositions and softcompounds thereof comprising a high amount of inorganic fillers.

BACKGROUND OF THE INVENTION

Polyolefin compositions having elastic properties while maintaining agood thermoplastic behavior have been used in many application fields,due to the valued properties which are typical of polyolefins, such aschemical inertia, mechanical properties and nontoxicity. Moreover, theycan be advantageously transformed into finished products with the sametechniques used for thermoplastic polymers. In particular, flexiblepolymer materials are widely used in the medical field, as well as forpackaging, extrusion coating and electrical wires and cables covering.In many of these applications, vinyl chloride polymers containingadequate plasticizers, which are necessary to give said polymers theirdesired flexibility characteristics, are presently used. Said polymerproducts, however, are subject to ever increasing criticism both for thesuspected toxicity of the plasticizers they contain and because whenincinerated, they can disperse into the atmosphere extremely toxicby-products, such as dioxin. It would be very useful, therefore, tosubstitute said materials with products which besides the desiredflexibility characteristics and transparency, would have the chemicalinertia and nontoxicity typical of olefin polymers. Elasticpolypropylene compositions retaining good thermoplastic behavior havebeen obtained in the art by way of sequential copolymerization ofpropylene, optionally containing minor quantities of olefin comonomers,and then ethylene/propylene or ethylene/alpha-olefin mixtures. Catalystsbased on halogenated titanium compounds supported on magnesium chlorideare commonly used for this purpose. For instance, EP-A-472 946 describesflexible elastoplastic polyolefin compositions comprising, in parts byweight: A) 10-50 parts of an isotactic propylene homopolymer orcopolymer; B) 5-20 parts of an ethylene copolymer, insoluble in xyleneat room temperature; and C) 40-80 parts of an ethylene/propylenecopolymer containing less than 40% by weight of ethylene and beingsoluble in xylene at room temperature; the intrinsic viscosity of saidcopolymer is preferably from 1.7 to 3 dl/g. Said compositions arerelatively flexible and have good elastic properties, as demonstrated byflexural modulus lower than 150 MPa values, Shore D hardness from 20 to35, and Shore A hardness of about 90, associated with good tension setvalues (of 20-50% at 75% elongation, and about 33-40% at 100%elongation); nevertheless, such values are not fully satisfactory formany applications. Mineral fillers, such as aluminum and magnesiumhydroxides or calcium carbonate, are commonly used at high concentrationlevels in polyolefin compositions for several reasons, for instance toimpart self-extinguishing properties or to improve application-relatedphysical properties, such as soft touch and printability. The majordisadvantage of these mineral fillers, in particular when used onfunctional grounds as in the case of flame retardants, is the very highloading needed. Depending on the class of fire-retardancy requested, upto 65-70% by weight of filler can be necessary in order to reachadequate effectiveness in polyolefins: A lower amount of filler around40-60% wt can be also sufficient for flame retardancy in certainapplications. Normally, this has a highly negative influence on theprocessing of the polymer, with difficulties in adding and dispersingsuch high levels of filler, and on the physical-mechanical properties ofcompounds, namely lower elongation at break, lower tensile strength andhigher brittleness. EP 1 043 733 describes self-extinguishing electricalcables having a coating layer based on a polymer material containing aflame-retardant inorganic filler; this polymer material comprises aheterophase copolymer having at least 45% by weight of an elastomericphase based on ethylene copolymerized with an alpha-olefin, and athermoplastic phase based on propylene. While these compositionsincorporate large amounts of flame-retardant filler, the very highlevels of filler negatively affect the physical-mechanical properties ofthe polymer material, and in particular lead to low elongation values.As a result, the final product is no longer apt to various applications,such as roofing, membranes and cables. In order to compete withplasticised PVC in the above applications, it would be necessary toprovide flexible polyolefin compositions, having low flexural modulusand hardness values, capable of incorporating large amounts of fillerwithout deterioration of physical and mechanical properties, and inparticular elongation at break, stress at break, tension set andimproved behaviour at low temperature.

More flexible elastoplastic polyolefin compositions have been describedin the International Application WO03/011962, and comprise, by weight:

A) 8 to 25% of a crystalline polymer fraction selected from propylenehomopolymer and propylene copolymers with a C4-8 alpha-olefin;

B) 75 to 92% of an elastomeric fraction comprising two differentpropylene elastomeric copolymers, and more specifically: (1) a firstelastomeric copolymer of propylene with 15 to 32% of ethylene and or aC4-8 alpha-olefin, and (2) a second elastomeric copolymer of propylenewith more than 32% up to 45% of ethylene and/or a C4-8 alpha-olefin, the(1)/(2) weight ratio ranging from 1:5 to 5:1. These polyolefincompositions have flexural modulus lower than 60 MPa, Shore A lower than90, and tension set at 100% elongation lower than 35%. The compositionsdescribed in this document do not contain relevant amounts of fillers.

In the International Application WO2004/026957 the flexible polyolefincompositions described in WO03/011962 are filled with 40 to 80% byweight of an inorganic filler, selected from flame-retardant inorganicfillers and inorganic oxides or salts, without loosing theirphysical-mechanical properties, and in particular retaining low hardnessand flexural modulus values, high elongation at break and low tensionset values. and The highly filled soft polyolefin compositions describedin WO2004/026957 have preferably Shore A hardness lower than 90,elongation at break (ASTM D638) higher than 400%, tensile strength atbreak (ASTM D638) equal to or higher than 4 MPa.

SUMMARY OF THE INVENTION

It is still felt the need of polyolefin compositions that, whenappropriately compounded with inorganic fillers, show improved balanceof properties particularly in applications where softness and ductilityat low temperature is requested without excessive deterioration of othermechanical properties such as particularly tensile properties.

Thus, it is an object of the present invention a flexible heterophasicpolyolefin composition (I), comprising the following fractions (whereinthe total of A and B fractions is 100%):

-   -   A) from 20 to 40%, preferably from 25 to 35% by weight of a        crystalline polymer fraction consisting of a propylene        homopolymer, or a copolymer of propylene with one or more        comonomers selected from ethylene and a CH₂═CHR alpha-olefin,        where R is a C₂-C₈ alkyl radical, or mixtures thereof; said        homopolymer or copolymer containing at least 85% by weight of        units derived from propylene, said crystalline fraction having a        fraction insoluble in xylene at 25° C. of at least 90% by        weight, preferably having intrinsic viscosity of the xylene        insoluble fraction of from 1.2 to 1.8 dl/g and preferably MFR        (230° C./2.16 Kg) of from 2 to 70, more preferably of from 20 to        50 g/10 min.    -   B) from 60 to 80%, preferably from 65 to 75% by weight of an        elastomeric fraction consisting of a copolymer or blend of        copolymers of ethylene with one or more comonomers selected from        propylene and CH₂═CHR alpha-olefins, where R is a C2-C8 alkyl        radical, and optionally with minor quantities of a diene; said        copolymers containing units derived from ethylene (i.e polymer        chain segments) in a quantity lower than 40% by weight, said        elastomeric fraction preferably having solubility in xylene at        room temperature (25° C.) greater than 50% by weight, and        preferably intrinsic viscosity of the soluble fraction η of        equal to or less than 2.3 dl/g.    -   the fraction soluble in xylene at 25° C. of said polyolefin        composition having IVgpc lower than 2.5 dl/g, preferably of from        1.7 to 2.2 dl/g; and a broad molecular weight distribution Mw/Mn        (GPC) equal to or higher than 4, preferably of from 4.2 to 6,        Mz/Mw (GPC) equal to or higher than 2.5.

The above said polyolefin composition preferably have MFR 230° C./2.16Kg of from 3 to 8 gr/10 min.

A further object of the present invention is a filled polyolefincomposition preferably having MFR 230° C./2.16 Kg of from 0.5 to 2 gr/10min comprising:

-   -   a) 20 to 60% by weight of the polyolefin composition (I)        according to the previous description, and    -   b) 40 to 80% by weight of an inorganic filler (II) selected from        flame-retardant inorganic fillers and inorganic oxides or salts,

wherein the total of a and b is 100%.

The above said broad molecular weight distribution of the fractionsoluble in xylene at room temperature of the elastomeric component B ispreferably obtained by blending two or more flexible heterophasicpolyolefin compositions having different xylene soluble intrinsicviscosities (XSIV=η), optionally and preferably obtainable by differentdegree of visbreaking. Particularly preferred is the blend of threeheterophasic compositions as hereinbelow described in detail.

The highly filled polyolefin compositions of the invention havepreferably Shore Hardness D lower than 50, elongation at break (ISO527-3, technically equivalent to the ASTM D638 norm) higher than 250%and tensile strength at break (ISO 527-3) equal to or higher than 10,preferably higher than 15 MPa and Tg-DSC lower than −40° C.

The filled composition of the present invention are particularlysuitable in application for roofing and geo-membrane where softness andductility of the material is essential. Particularly advantageously theywill find use in sites with rigid climate or broad seasonal or dailyvariations of temperature.

DETAILED DESCRIPTION OF THE INVENTION

The heterophasic polyolefin composition of the invention are able toincorporate and retain high amount of inorganic filler, maintaining verylow flexural modulus values and flexible behavior and, at the same timeexerting the property imparted by the filler, such as self-extinguishingproperties in case of flame-retardant fillers, which is essential formost cable applications, roofing applications and soft sheeting.Moreover, the compositions of the invention, at comparable values oftensile strength, show elongation at break values equal to or higherthan the ones shown by the filled compositions known in the prior art.Finally, the compositions of the invention are endowed with good lowtemperature behaviour in terms of lower glass transition temperature(DSC-Tg) and improved ductility at puncture impact behaviour test.

The polyolefin composition (I) according to the invention is anheterophasic composition comprising the following fractions:

-   -   A) from 20 to 40, preferably 25 to 35% by weight of a        crystalline polymer fraction consisting of a propylene        homopolymer, or a copolymer of propylene with one or more        comonomers selected from ethylene and a CH₂═CHR alpha-olefin,        where R is a C₂-C₈ alkyl radical, or mixtures thereof; said homo        or copolymer containing at least 85% by weight of units derived        from propylene, said crystalline fraction having a fraction        insoluble in xylene at 25° C. of at least 90% by weight,        preferably having intrinsic viscosity of the xylene insoluble        fraction (XinsIV) of from 1.2 to 1.8 dl/g and preferably MFR        (230° C./2.16 Kg) of from 2 to 70, more preferably of from 20 to        50 g/10 min;    -   B) from 60 to 80%, preferably from 65 to 75% by weight of an        elastomeric fraction consisting of a copolymer or blend of        copolymers of ethylene with one or more comonomers selected from        propylene and CH₂═CHR alpha-olefins, where R is a C₂-C₈ alkyl        radical, and optionally with minor quantities of a diene; said        copolymer or blend containing units derived from ethylene in a        quantity equal to or less than 40% by weight;    -   wherein the total of A and B fractions is 100%,    -   the fraction soluble in xylene at 25° C. of said polyolefin        composition having IVgpc the Intrinsic Viscosity of the fraction        soluble in xylene at 25° C., measured by gel permeation        chromatography (GPC), equal to or less than 2.5 dl/g, preferably        of from 1.7 to 2.2 dl/g; the ratio Mw/Mn of weight average        molecular weight (Mw) to number average molecular weight (Mn)        measured by gel permeation chromatography (GPC) equal to or more        than 4, preferably of from 4.2 to 6, the ratio Mz/Mw of        Z-average molecular weight (Mz) to weight average molecular        weight (Mw) measured by gel permeation chromatography (GPC)        equal to or more than 2.5.

By “elastomeric” is meant herein a polymer having low crystallinity oramorphous, preferably having solubility in xylene at 25° C. greater than50%, preferably greater than 60% by weight. More preferably, andalternatively to the IVgpc value, the intrinsic viscosity η of theXylene soluble fraction at 25° C. of the compositions according to theinvention can be measured and is equal to or less than 2.3 dl/g,preferably equal to or less than 2.1, even more preferably of from 1.5to 2.1 dl/g.

According to a preferred embodiment of the composition (I) according tothe present invention, the elastomeric fraction (B) comprises two ormore, preferably three components B1, B2 and B3. The intrinsic viscosityη of the fraction soluble in xylene at 25° C. of B1, B2 and B3, measuredas described in the experimental part, being respectively:

(η_(B1)) equal to or greater than 3, preferably from 3 to 10 dl/g;

(η_(B2)) from 2 to 3 dl/g;

(η_(B3)) equal to or less than 2, preferably from 1.5 to 2 dl/g,

Further preferably the intrinsic viscosities (IVgpc) of the fractionsoluble in xylene at 25° C. of B1, B2 and B3 measured via GPC, asdescribed in the experimental part, are respectively:

IVgpc of B1 is equal to or greater than 2.5 dl/g,

IVgpc of B2 is of from 1.5 to 2.5 dl/g and

IVgpc of B3 is equal to or less than 1.5 dl/g

The composition (I) according to the invention preferably have MFR 230°C./2.16 Kg of from 3 to 8 gr/10 min.

In the polyolefin composition (I), said alpha-olefin of formula H₂C═CHRis preferably selected from, butene-1, pentene-1,4-methylpentene,hexene-1, octene-1 and combinations thereof.

The copolymerization of propylene and ethylene or another alpha-olefinor combinations thereof, to form the elastomeric fraction (B), or thepreferred copolymer components B1, B2 and B3 can occur in the presenceof a diene, conjugated or not, such as butadiene, 1,4-hexadiene,1,5-hexadiene and ethylidene-norbornene-1. The diene, when present, iscontained in an amount of from 0.5 to 5% by weight, with respect to theweight of the fraction (B).

According to a preferred embodiment of the invention, the heterophasicpolyolefin composition (I) is in the form of spheroidal particles havingan average diameter of 250 to 7,000 microns, a flowability of less than30 seconds and a bulk density (compacted) greater than 0.4 g/ml. Theheterophasic polyolefin composition (I) may be prepared bypolymerization in sequential polymerization stages, with each subsequentpolymerization being conducted in the presence of the polymeric materialformed in the immediately preceding polymerization reaction. Thepolymerization stages may be carried out in the presence of aZiegler-Natta and/or a metallocene catalyst. According to a preferredembodiment, all the polymerization stages are carried out in thepresence of a catalyst comprising a trialkylaluminum compound,optionally an electron donor, and a solid catalyst component comprisinga halide or halogen-alcoholate of Ti and an electron donor compoundsupported on anhydrous magnesium chloride, said solid catalyst componenthaving a surface area (measured by BET) of less than 200 m2/g, and aporosity (measured by BET) higher than 0.2 ml/g. Catalysts having theabove mentioned characteristics are well known in the patent literature;particularly advantageous are the catalysts described in U.S. Pat. No.4,399,054 and EP-A-45 977. Other examples can be found in U.S. Pat. No.4,472,524. The polymerization process is described in details in theInternational Application EP-A-472946, the content of which isincorporated herein by reference. The solid catalyst components used insaid catalysts comprise, as electron-donors (internal donors), compoundsselected from the group consisting of ethers, ketones, lactones,compounds containing N, P and/or S atoms, and esters of mono- anddicarboxylic acids. Particularly suitable electron-donor compounds arephthalic acid esters, such as diisobutyl, dioctyl, diphenyl andbenzylbutyl phthalate.

Other electron-donors particularly suitable are 1,3-diethers of formula:

wherein RI and RII, the same or different from each other, are C₁-C₁₈alkyl, C₃-C₁₈ cycloalkyl or Cr C₁₋₈ aryl radicals; RIII and RIV, thesame or different from each other, are C₁-C₄ alkyl radicals; or are the1,3-diethers in which the carbon atom in position 2 belongs to a cyclicor polycyclic structure made up of 5, 6 or 7 carbon atoms and containingtwo or three unsaturations. Ethers of this type are described inEP-A-361 493 and EP-A-728 769. Representative examples of said diethersare 2-methyl-2-isopropyl-1,3-dimethoxypropane,2,2-diisobutyl-1,3-dimethoxypropane,2-isopropyl-2-cyclopentyl-1,3-dimethoxypropane,2-isopropyl-2-isoamyl-1,3-dimethoxypropane, and9,9-bis(methoxymethyl)fluorene. The preparation of the above mentionedcatalyst components is carried out according to known methods. Forexample, a MgCl₂.nROH adduct (in particular in the form of spheroidalparticles) wherein n generally ranges from 1 to 3 and ROH is ethanol,butanol or isobutanol, is reacted with an excess of TiCl₄ containing theelectron-donor compound. The reaction temperature is generally comprisedbetween 80 and 120° C. The solid is then isolated and reacted once morewith TiCl₄, in the presence or absence of the electron-donor compound;it is then separated and washed with a hydrocarbon until all chlorineions have disappeared.

In the solid catalyst component the titanium compound, expressed as Ti,is generally present in an amount from 0.5 to 10% by weight. Thequantity of electron-donor compound which remains fixed on the solidcatalyst component generally is 5 to 20% by moles with respect to themagnesium dihalide. The titanium compounds which can be used in thepreparation of the solid catalyst component are the halides and thehalogen alcoholates of titanium. Titanium tetrachloride is the preferredcompound. The reactions described above result in the formation of amagnesium halide in active form. Other reactions are known in theliterature, which cause the formation of magnesium halide in active formstarting from magnesium compounds other than halides, such as magnesiumcarboxylates.

The Al-alkyl compounds used as co-catalysts comprise Al-trialkyls, suchas Al-triethyl, Al-triisobutyl, Al-tri-n-butyl, and linear or cyclicAl-alkyl compounds containing two or more Al atoms bonded to each otherby way of O or N atoms, or SO₄ or SO₃ groups. The Al-alkyl compound isgenerally used in such a quantity that the Al/Ti ratio is from 1 to1000. Electron-donor compounds that can be used as external donorsinclude aromatic acid esters such as alkyl benzoates, and in particularsilicon compounds containing at least one Si—OR bond, where R is ahydrocarbon radical. Examples of silicon compounds are(tert-butyl)₂Si(OCH₃)₂, (cyclohexyl)(methyl)Si(OCH₃)₂,(phenyl)₂Si(OCH₃)₂ and (cyclopentyl)₂ Si(OCH₃)₂. 1,3-diethers having theformulae described above can also be used advantageously. If theinternal donor is one of these dieters, the external donors can beomitted. The solid catalyst component have preferably a surface area(measured by BET) of less than 200 m²/g, and more preferably rangingfrom 80 to 170 m²/g, and a porosity (measured by BET) preferably greaterthan 0.2 ml/g, and more preferably from 0.25 to 0.5 ml/g.

The catalysts may be precontacted with small quantities of olefin(prepolymerization), maintaining the catalyst in suspension in ahydrocarbon solvent, and polymerizing at temperatures from roomtemperature to 60° C., thus producing a quantity of polymer from 0.5 to3 times the weight of the catalyst. The operation can also take place inliquid monomer, producing, in this case, a quantity of polymer 1000times the weight of the catalyst. By using the above mentionedcatalysts, the polyolefin compositions are obtained in spheroidalparticle form, the particles having an average diameter from about 250to 7,000 microns, a flowability of less than 30 seconds and a bulkdensity (compacted) greater than 0.4 g/ml.

The polymerization stages may occur in liquid phase, in gas phase orliquid-gas phase. Preferably, the polymerization of the crystallinepolymer fraction (A) is carried out in liquid monomer (e.g. using liquidpropylene as diluent), while the copolymerization stages of theelastomeric copolymer(s) in fraction (B) are carried out in gas phase,without intermediate stages except for the partial degassing of thepropylene. According to a most preferred embodiment, all the sequentialpolymerization stages are carried out in gas phase.

The reaction temperature in the polymerization stage for the preparationof the crystalline polymer fraction (A) and in the preparation of theelastomeric copolymer(s) in fraction (B) can be the same or different,and is preferably from 40° C. to 90° C.; more preferably, the reactiontemperature ranges from 50 to 80° C. in the preparation of the fraction(A), and from 40 to 80° C. for the preparation of components (B). Thepressure of the polymerization stage to prepare the fraction (A), ifcarried out in liquid monomer, is the one which competes with the vaporpressure of the liquid propylene at the operating temperature used, andit may be modified by the vapor pressure of the small quantity of inertdiluent used to feed the catalyst mixture, by the overpressure ofoptional monomers and by the hydrogen used as molecular weightregulator.

The polymerization pressure preferably ranges from 33 to 43 bar, if donein liquid phase, and from 5 to 30 bar if done in gas phase. Theresidence times relative to the two stages depend on the desired ratiobetween the fractions (A) and (B), and can usually range from 15 minutesto 8 hours. Conventional molecular weight regulators known in the art,such as chain transfer agents (e.g. hydrogen or ZnEt2), may be used.

The preferred composition according to the present invention havingcomponent A and an elastomeric fraction made of components B1 B2 and B3can be obtained with the above described process in four stages; onestage for the production of component (A) and three for the productionof three elastomeric components B1 B2 and B3 having the required valuesof intrinsic viscosities.

Alternatively the composition according to the invention can be obtainedby separate production of the components and subsequent blending e.g.melt blending in conventional extrusion or mixing equipments. Sequentialpolymerization and melt blending steps can be also used in mixedsequential and melt blending processes for the production of thecomposition according to the invention.

Alternatively and even more preferably, an heterophasic compositionaccording to the invention can be obtained producing an heterophasiccomposition HPO1, obtainable as a reactor blend by sequentialpolymerization as described in EP-A-472946, comprising:

-   -   A) from 20 to 40, preferably from 25 to 35% by weight of a        crystalline polymer fraction consisting of a propylene        homopolymer, or a copolymer of propylene with one or more        comonomers selected from ethylene and a CH₂═CHR alpha-olefin,        where R is a C₂-C₈ alkyl radical, or mixtures thereof; said        (co)polymers containing at least 85% by weight of units derived        from propylene, said crystalline fraction having a fraction        insoluble in xylene at 25° C. of at least 90% by weight,        preferably having intrinsic viscosity of the xylene insoluble        fraction (XinsIV) of from 1.2 to 1.8 dl/g and preferably MFR        (230° C./2.16 Kg) of from 2 to 70, more preferably of from 20 to        50 g/10 min, even more preferably greater than 25 g/10 min.    -   B) from 60 to 80%, preferably from 65 to 75% by weight of an        elastomeric fraction consisting of a copolymer of ethylene with        one or more comonomers selected from propylene and CH₂═CHR        alpha-olefins, where R is a C₂-C₈ alkyl radical, and optionally        with minor quantities of a diene, or mixtures thereof; said        copolymer containing units derived from ethylene in a quantity        equal to or less than 40% by weight;        The said composition HPO1 having MFR1 (290° C./2.16 Kg) of equal        to or less than 5, preferably of less than 1 gr/10 min and        Xylene Soluble Intrinsic Viscosity (XSIV η₁) of equal to or        greater than 3. Suitable as composition HPO1 is an heterophasic        polyolefin composition commercialized by Basell under the        commercial name Hifax CA10A.

The above said composition HPO1 can be subsequently visbroken viaperoxide treatment producing further heterophasic compositions:

HPO2 having MFR2 values of from 5 to 10 g/10 min and XSIV η₂ of from 2to 3 dl/g, and HPO3 having MFR3 values equal to or higher than 10 g/10min and XSIV η₃ of equal to or less than 2 dl/g. The said compositionsHPO1, HPO2 and HPO3 are blended in proportion of25-50% wt of HPO1, preferably 30-40% wt25-50% wt of HPO2, preferably 30-40% wt and25-50% wt of HPO3, preferably 30-40% wtwherein the total of HPO1, HPO2 and HPO3 is 100%, providing thecomposition (I) according to the invention. It is assumed that η₁, η₂,η₃ are substantially corresponding to the values of (η_(B1)), (η_(B2)),and (η_(B3)) due to the very low xylene solubility of component A.

The further object of the present invention is a highly filled softpolyolefin composition comprising from 20 to 60% by weight, preferablyfrom 30 to 50%, and even more preferably from 30 to 35% of thecomposition (I) as above described and from 40 to 80% by weight,preferably from 50 to 70%, and even more preferably from 65 to 70% of aninorganic filler (II) selected from flame-retardant inorganic fillersand inorganic oxides or salts; wherein the total of a and b is 100%.

In applications where self-extinguishing properties are required,preferred flame-retardant inorganic fillers are hydroxides, hydratedoxides, salts or hydrated salts of metals, in particular of Ca, Al orMg, such as, for example: magnesium hydroxide Mg(OH)₂, aluminumhydroxide Al(OH)₃, alumina trihydrate Al₂O₃.3H₂0, magnesium carbonatehydrate, magnesium carbonate MgCO3, magnesium calcium carbonate hydrate,magnesium calcium carbonate, or mixtures thereof. Mg(OH)₂, Al(OH)₃,Al₂O₃.3H₂0 and mixtures thereof are particularly preferred. The metalhydroxides, in particular the magnesium and aluminium hydroxides, arepreferably used in the form of particles with sizes which can rangebetween 0.1 and 100 μm, preferably between 0.5 and 10 μm. One inorganicfiller which is particularly preferred according to the presentinvention is a precipitated magnesium hydroxide, having specific surfacearea of from 1 to 20 m²/g, preferably from 3 to 10 m²/g, an averageparticle diameter ranging from 0.5 to 15 μm, preferably from 0.6 to 1μm. and the Precipitated magnesium hydroxide generally contains very lowamounts of impurities deriving from salts, oxides and/or hydroxides ofother metals, such as Fe, Mn, Ca, Si, V, etc. The amount and nature ofsuch impurities depend on the origin of the starting material. Thedegree of purity is generally between 90 and 99% by weight. The fillercan be advantageously used in the form of coated particles. Coatingmaterials preferably used are saturated or unsaturated fatty acidscontaining from 8 to 24 carbon atoms, and metal salts thereof, such as,oleic acid, palmitic acid, stearic acid, isostearic acid, lauric acid,and magnesium or zinc stearate or oleate. Inorganic oxides or salts arepreferably selected from CaO, TiO₂, Sb₂O₃, ZnO, Fe₂O₃, CaCO₃, BaSO₄ andmixtures thereof.

The highly filled soft polyolefin compositions according to the presentinvention can be prepared by mixing the polymer component, the fillerand optionally further additives according to methods known in the stateof the art. For instance, the components may be mixed in an internalmixer having tangential rotors (such as Banbury mixers) or havinginterpenetrating rotors, or alternatively in continuous mixers (such asBuss mixers) or co-rotating or counter-rotating twin-screw mixers. Thehighly filled soft polyolefin compositions of the invention, having verylow initial flexural modulus values, are capable of incorporating largeamounts of fillers, at the same time retaining the physical andmechanical properties of unfilled and less flexible compositions. Morespecifically, the highly filled polyolefin compositions of the inventionare preferably endowed with Shore D Hardness lower than 50 (ISO 868),more preferably lower than 48; elongation at break (ISO 527-3) higherthan 250%, more preferably higher than 280%; even more preferably higherthan 290%, tensile strength at break (ISO 527-3) equal to or higher than10 MPa, more preferably higher than 15 MPa.

Moreover, the polyolefin compositions of the invention preferably haveflexural modulus (ISO 178 on compression molded samples 1 mm thick) oflower than 600 MPa, more preferably from 300 to 600 MPa. A furthercharacteristic of the highly filled polyolefin compositions of theinstant invention is that they are capable of retaining ductile behaviorat very low temperature having Tg-DSC values lower than −40° C. Thepolyolefin compositions of the present invention find application asplasticized PVC replacement. In fields where self-extinguishingproperties are required, the compositions of the invention may be usedin lieu of plasticized PVC, in applications such as reinforced andnonreinforced roofing membranes, inner filling for industrial cables,cable sheathing and adhesive tapes. Where flame-retardancy is notrequested, the compositions of the invention may be advantageously usedin non flame-retardant soft membranes, coupled or non-coupled with areinforcement (e.g. in publicity banners, liners, tarpaulin, sport-wearand safety clothing), and as synthetic leather. Moreover, thecompositions may be used in packaging and extrusion coating.

Therefore, the present invention is further directed to an articlecomprising the above described polyolefin composition. Specifically andpreferably it is also directed to blown or cast film or sheets suitablefor application in the field of roofing and geomembrane, requiringflexibility softness and ductility at low temperature.

Conventional additives commonly used in the state of the art may beadded to the highly filled soft polyolefin compositions of the presentinvention. For instance, in order to enhance the compatibility betweenthe inorganic filler and the heterophasic polymer composition, couplingagents may be used; said coupling agents may be saturated silanecompounds or silane compounds containing at least one ethylenicunsaturation, epoxides containing an ethylenic unsaturation, organictitanates, mono- or dicarboxylic acids containing at least one ethylenicunsaturation, or derivatives thereof such as anhydrides or esters.

Mono- or dicarboxylic acids containing at least one ethylenicunsaturation, or derivatives thereof, which can be used as couplingagents are, for example, maleic acid, maleic anhydride, fumaric acid,citraconic acid, itaconic acid, acrylic acid, methacrylic acid and thelike, and the anhydrides or esters derived therefrom, or mixturesthereof. Maleic anhydride is particularly preferred.

The coupling agents can be used as such or pre grafted onto apolyolefin, for example polyethylene or copolymers of ethylene with analpha-olefin, by means of a radical reaction (as described for instancein EP-A-530 940. The amount of grafted coupling agent is generallycomprised between 0.05 and 5 parts by weight, preferably from 0.1 to 2parts by weight, relative to 100 parts by weight of polyolefin.Polyolefins grafted with maleic anhydride are commonly available ascommercial products, such as Polybond 3200 produced by Chemtura orQestron by Basell.

Alternatively, the coupling agents of carboxylic or epoxy type mentionedabove (for example maleic anhydride) or silanes containing an ethylenicunsaturation (for example vinyltrimethoxysilane) can be added to themixture in combination with a radical initiator so as to graft thecompatibilizing agent directly onto the polymer material. Initiatorswhich can be used are organic peroxides, such as tert-butyl perbenzoate,dicumyl peroxide, benzoyl peroxide, di-tert-butyl peroxide and the like.This technique is described, for example, in U.S. Pat. No. 4,317,765.

The amount of coupling agent to be added to the mixture may varyaccording to the nature of the coupling agent used and the amount offlame-retardant filler added, and preferably ranges from 0.01 to 10%,more preferably from 0.1 to 5%, and even more preferably from 1 to 3% byweight with respect to the total weight of the highly filled polyolefincomposition. Depending on the properties needed for the differentapplications, the compositions of the invention may be used in furthercombination with other elastomeric polymers such as ethylene/propylenecopolymers (EPR), ethylene/propylene/diene terpolymers (EPDM),copolymers of ethylene with C₄-C₁₂ alpha-olefins (e.g. ethylene/octene-1copolymers, such as the ones commercialized under the name Engage®) andmixtures thereof. Such elastomeric polymers may be present in an amountof 5 to 80% wt. of the total composition. Particularly preferred, addedin amount from 1-30% wt of the total composition, are elastomericcopolymers having flexural elastic modulus (MEF) equal to or less than30 MPa and Shore A Hardness equal to or lower than 90, preferably lowerthan 70. Suitable elastomeric copolymers are metallocene butene-1(co)polymer plastomers such as those described in EP-B-2158235 and softheterophasic polypropylene polymers such as those described inWO03/011962. The effect of the addition of the said elastomericmaterials is that the improvement of certain properties (e.g elongation)is obtained without deterioration of softness and ductilility at lowtemperature.

Conventional additives such as processing aids, lubricants, nucleatingagents, extension oils, organic and inorganic pigments, anti-oxidantsand UV-protectors, commonly used in olefin polymers, may also be added.

Processing aids usually added to the polymer material are, for example,calcium stearate, zinc stearate, stearic acid, paraffin wax, syntheticoil and silicone rubbers. Examples of suitable antioxidants arepolymerized trimethyldihydroquinoline,4,4′thiobis(3-methyl-6-tert-butyl)phenol;pentaerythrityltetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]and2,2′-thiodiethylenebis[3-(3,5-di-tertbutyl-4-hydroxyphenyl)propionate].Other fillers which can be used are, for example, glass particles, glassfibers, calcinated kaolin and talc.

The following analytical methods have been used to determine theproperties reported in the present application.

Property Method

Melt Flow Rate

ISO1133, at 230° C., 2.16 kg where not differently specified

MWD and IV Determination Via GPC

-   -   The Mn, Mw and Mz and IVgpc values are measured by way of gel        permeation chromatography (GPC) at 150° C. using a Alliance GPCV        2000 instrument (Waters) equipped with four mixed-bed columns        PLgel Olexis Agilent having a particle size of 13 μm. The        dimensions of the columns are 300×7.8 mm. The mobile phase used        is vacuum distilled 1,2,4-Trichlorobenzene (TCB) and the flow        rate is kept at 1.0 ml/min. The sample solution is prepared by        heating the sample under stirring at 150° C. in TCB for about        two hours. The concentration is 1 mg/ml. To prevent degradation,        0.1 g/l of 2,6-diterbutyl-p-cresol are added. 308.5 μL of        solution are injected into the column set. A calibration curve        is obtained using 10 polystyrene standard samples (EasyCal kit        by Polymer Laboratories) with molecular weights in the range        from 580 to 7500000. It is assumed that the K values of the        Mark-Houwink relationship are:        K=1.21×10⁻⁴ dL/g and α=0.706 for the polystyrene standards;        K=2.46×10⁻⁴ dL/g and α=0.725 for the propylene copolymer        samples.

A third order polynomial fit is used for interpolate the experimentaldata and obtain the calibration curve. Data acquisition and processingis done by using Empower 1.0 with GPCV option by Waters.

Low Temperature Impact Properties:

-   -   The impact properties were measured according to the ISO 6603        (Puncture Impact Behavior of Rigid Plastics) on samples obtained        from 1 mm sheets extruded on a Brabender 30 mm, 25 L/D single        screw extruder with 1 mm thick flat die, and cut in machine        direction. The instrumental apparatus for the impact measurement        was a CEAST-Fractovis INSTRON instrumented unit that allows to        distinguish between ductile and brittle failure modes according        to ISO 6603 without need for subjective judgments.

The modes of failure are:

-   -   Ductile (YD)    -   Ductile/Brittle (YS)    -   Brittle/Ductile (YU)    -   Brittle (NY)

The fracture mode was recorded for 10 samples per each compositiontested.

Tensile Properties:

-   -   Tensile Strength at Break and Elongation at Break, were measured        following the ISO 527-3 (item 5A, 500 mm/min), on samples        obtained from 1 mm sheets extruded on a Brabender 30 mm, 25 L/D        single screw extruder with 1 mm thick flat die, and cut and        tested in machine direction.

Hardness Shore A (Sh.A) and Shore D (Sh.D)

-   -   measured on a compression moulded plaques (thickness of 4 mm)        following the ISO 868.

Tg-DSC

-   -   the glass transition temperature (Tg) was measured via DSC        performed at 10° C./min. The Tg was determined after cooling        starting from −90° C.

Tensile Elastic Modulus (MET-DMTA)

-   -   Tensile Elastic Modulus (storage modulus) determined at 23° C.        via DMA analysis according to the ISO 6721-4 on 1 mm thick        compression moulded plaque.

Flexural Elastic Modulus (MEF)

-   -   ISO 178 on 1 mm thick compression moulded plaque.

Comonomer Content (% wt)

-   -   IR. Spectroscopy

Intrinsic Viscosity

-   -   Determined in tetrahydronaphthalene at 135° C. for the insoluble        fractions (XinsIV) and for the xylene soluble fractions        (XSIV=η). XSIV=η of the compositions (I) according to the        invention, are assumed to correspond substantially to the        viscosity of the solubles of the elastomeric fraction        component(s) B.

Xylene Soluble and Insoluble Fractions (% Wt)

-   -   determined as follows:    -   2.5 g of polymer composition and 250 cm³ of O-xylene are        introduced in a glass flask equipped with a refrigerator and a        magnetical stirrer. The temperature is raised in 30 minutes up        to the boiling point of the solvent. The so obtained clear        solution is then kept under reflux and stirring for further 30        minutes. The closed flask is then cooled to 100° C. in air for        10 to 15 minute under stirring and then kept for 30 minutes in        thermostatic water bath at 25° C. for 30 minutes as well. The so        formed solid is filtered on quick filtering paper. 100 cm3 of        the filtered liquid is poured in a previously weighed aluminum        container which is heated on a heating plate under nitrogen        flow, to remove the solvent by evaporation. The container is        then kept in an oven at 80° C. under vacuum until constant        weight is obtained. The weight percentage of polymer soluble in        xylene (XS) at room temperature (25° C.) is then calculated.

Products Used in Working Examples

HPO1: Heterophasic polyolefin composition having MFR 0.8 g/10 min, MEF80 MPa, Hardness Shore D (Sh.D) 30, η_(B1) 3.3 dl/g, Mw/Mn 5.8, Mz/Mw2.4, IVgpc 2.78 dl/g; and comprising 31% wt. of A1 a crystallinecopolymer of propylene with 3.3% wt. of units derived from ethylene,having MFR A1 25 g/10 min, a soluble fraction in xylene at 25° C. of 6%wt, and XinsIV 1, 8 dl/g, and 69% wt. of B1 an elastomeric fraction ofpropylene with ethylene having 27% by weight of units derived fromethylene, 89% wt of fraction soluble in xylene at 25° C.

-   -   HPO2: Heterophasic polyolefin composition having MFR (230° C.,        2.16 kg) of 8 g/10 min MEF 80 MPa, Shore D Hardness (Sh.D) 30;        obtained by slight visbreaking HPO1 via peroxide treatment        during pelletization, and further having after visbreaking        η_(B2) 2.8 dl/g, Mw/Mn 4.0, Mz/Mw 2.2, IVgpc 1.90 dl/g.    -   HPO3: Heterophasic polyolefin composition having MFR (230° C.,        2.16 kg) of 14 g/10 min MEF 80 MPa, Shore D Hardness (Sh.D) 30,        obtained by visbreaking HPO1 via peroxide treatment during        pelletization, and having η_(B3) 1.75 dl/g, Mw/Mn 3.40, Mz/Mw        2.1, IVgpc 1.48 dl/g.    -   Mg(OH)2: Kisuma 5A-C by Kyowa Chemical Industry, precipitated        magnesium hydroxide coated with fatty acid for compatibilization        with polyolefins having average particle size of 0.94 μm, purity        97.65%.    -   Processing Aid: Propylene homopolymer grafted with maleic        anhydride (MA), with MFR (190° C., 2.16 Kg) of 115 g/10 min and        MA content of 1% weight (Polybond 3200, sold by Chemtura).    -   Stabilizer: Irganox B215 commercialized by Ciba.

Example 1

A polyolefin composition according to the present invention was obtainedby blending in a Leistritz 27 mm twin screw extruder the heterophasicpolyolefin compositions HPO1, HPO2 and HPO3 and the mineral filler andadditives as reported in Table 1. The mechanical and thermal propertiesof this composition is reported in Table 1.

Comparative Example 2

An highly filled polyolefin composition according to the invention wasobtained by blending in a Leistritz 27 mm twin screw extruder theheterophasic polyolefin composition HPO2 and the mineral filler andadditives as reported in Table 1. The mechanical and thermal propertiesof this composition is reported in Table 1.

Comparative Example 3

Polyolefin composition similar to the one prepared in Example 2 wasobtained, with the exception that the heterophasic polymer compositionHPO1 was used. The mechanical and thermal properties of thiscompositions are reported in Table 1.

Comparative Examples 4-6

Polyolefin compositions were obtained, for comparative purposes, byblending a commercial crystalline propylene random copolymer withethylene derived units in amount equal to 3% wt, insolubility in xyleneat 25° C. of 96% wt and MFR (230° C., 2.16 Kg) of 8 g/10 min, withcommercial elastomeric polymers produced by Dow Chemicals having thefollowing properties:

Engage 8180 propylene ethylene copolymer with 38% ethylene, MFR (190°C./2.16 Kg) 0.5 g/10 min, MEF 8.5 MPa, Sh.A 63, Sh.D 16 and NarrowMolecular Weight Distribution (MWD=Mw/Mn) of 2 to 3

Versify 2300 propylene ethylene copolymer with 13.1% wt ethylene MFR(230° C., 2.16 Kg) of 2 g/10 min, MEF 42 MPa, Sh.A 88, Sh.D 32 andNarrow Molecular Weight Distribution (MWD=Mw/Mn) 2.8, Mz/Mw 1.9, IVgpc1.44.

Versify 3401 a propylene ethylene octene copolymer with 24% wt ofethylene, 3-4% wt octene, MFR L 8 g/10 min, MEF 22 MPa, Sh.A 72, Sh.D 22and Narrow Molecular Weight Distribution (MWD=Mw/Mn) 3, Mz/Mw 2, IVgpc1.90.

The mechanical and elastic properties of these compositions are reportedin Table 1.

All the highly filled compositions show similarly high stress at break(about 16 Mpa), Elongation at break is maintained sufficiently high,while surprisingly low Tg values are exhibited by the highly filledcomposition of the present invention in combination with substantiallyimproved ductility at low temperature that is not showed by thecomparative compositions.

TABLE 1 COMP. COMP. COMP. COMP. COMP. EX. 2 EX. 3 EX. 1 EX. 4 EX. 5 EX.6 COMPONENTS (% WT) Raco MIL 8 C2 = 3% % wt 9.85 15 13 HPO1 % wt 45.8514 HPO3 % wt 17.85 HPO2 % wt 45.85 14 ENR8180 % wt 9.425 Versify2300 %wt 36 21.425 Versify3401 % wt 32.85 C-KISUMA 5A Mg(OH)₂ % wt 50 50 50 5050 50 IRGANOX B215 % wt 0.15 0.15 0.15 0.15 0.15 0.15 polybond 3200 % wt4 4 4 4 4 4 Properties MFR (MIL) 230° C./2.16 kg gr/10′ 2.2 0.3 1.3 10.88 2.4 IVgpc* dl/g 1.90 2.78 2.02 Mw/Mn* 4.0 5.8 4.5 Mz/Mw* 2.2 2.42.6 Mw* 262284 450171 293237 Mz* 579200 1073385 775710 Mn* 65019 7781165020 FAILURE TEST ISO 6603 Temperature ° C. −40 −40 −40 −40 −40 −40 B(YU) Num 6 1 10 0 0 0 C (NY) Num 4 9 0 10 10 10 Temperature ° C. −30 −30−30 −30 −30 −30 D (YS) Num 0 0 0 0 7 0 B (YU) Num 10 10 10 1 3 8 C (NY)Num 0 0 0 9 0 2 Temperature ° C. −20 −20 −20 −20 −20 −20 D (YS) Num 2 1010 0 10 10 B (YU) Num 8 0 0 9 0 0 C (NY) Num 0 0 0 1 0 0 Tensile stress@ yield MPa 12.1 12 12.3 11.5 13.2 10.8 Elongation @ yield % 16 13.2 1620 14 15.1 Tensile stress @ break MPa 15.3 18.7 16.9 23.3 20.4 15Elongation @ break % 240 315 295 440 405 280 Shore D Hardness- 44.2 4646.4 54.1 50.6 46.2 Tg-DSC Data ° C. −42.8 −41.3 −32.5 −32.6 −38.5MET-DMTA (23° C.) MPa 612 636 600 557 443 *GPC data measured on thefraction Xylene Soluble at 25° C. of the polymer blend without additiveand filler-Kisuma.

1. A polyolefin composition comprising a polyolefin composition (I),wherein the polyolefin composition (I) comprises the followingfractions: A) from 20 to 40% by weight of a crystalline polymer fractionselected from the group consisting of a propylene homopolymer, and acopolymer of propylene with one or more comonomers selected fromethylene and a CH₂═CHR alpha-olefin, where R is a C₂-C₈ alkyl radical,or mixtures thereof, wherein the homopolymer or copolymer containing atleast 85% by weight of units derived from propylene, wherein thecrystalline fraction has a fraction insoluble in xylene at 25° C. of atleast 90% by weight; B) from 60 to 80% by weight of an elastomericfraction comprising a copolymer or blends of copolymers of ethylene withone or more comonomers selected from propylene and CH₂═CHRalpha-olefins, where R is a C₂-C₈ alkyl radical, and optionally withminor quantities of a diene; said copolymer or blend containing unitsderived from ethylene in a quantity equal to or less than 40% by weight;wherein the total weight of A and B fractions is 100%, and the fractionsoluble in xylene at 25° C. of said polyolefin composition has IVgpclower than 2.5 dl/g, the ratio Mw/Mn of weight average molecular weight(Mw) to number average molecular weight (Mn) measured by gel permeationchromatography (GPC) equal to or more than 4, and the ratio Mz/Mw ofZ-average molecular weight (Mz) to weight average molecular weight (Mw)measured by gel permeation chromatography (GPC) equal to or greater than2.5.
 2. The polyolefin composition according to claim 1 wherein theelastomeric fraction B has a solubility in xylene at room temperaturegreater than 50% by weight.
 3. The polyolefin composition according toclaim 1, wherein the elastomeric fraction (B) comprises at least threecomponents B1, B2 and B3, wherein the intrinsic viscosity, η, of thexylene soluble fraction of B1 is (η_(B1)) equal to or higher than 3dl/g; wherein the intrinsic viscosity, η, of the xylene soluble fractionof B2 is (η_(B2)) from 2 to 3 dl/g; and wherein the intrinsic viscosity,η, of the xylene soluble fraction of B3 is (η_(B3)) equal to or lowerthan 2 dl/g.
 4. The polyolefin composition according to claim 1, whereinthe polyolefin composition (I) has a MFR 230° C./2.16 Kg of from 3 to 8g/10 min.
 5. The polyolefin composition according to claim 1, whereinthe polyolefin composition comprises: 20 to 60% by weight of thepolyolefin composition (I), and 40 to 80% by weight of an inorganicfiller (II) selected from flame-retardant inorganic fillers andinorganic oxides or salts.
 6. The polyolefin composition according toclaim 5, wherein the inorganic filler (II) is a flame-retardantinorganic filler selected from hydroxides, hydrated oxides, salts andhydrated salts of metals.
 7. The polyolefin composition according toclaim 5, wherein the flame-retardant inorganic filler is selected fromMg(OH)₂, Al(OH)₃, Al₂O₃.3H₂0, magnesium carbonate hydrate, MgCO₃,magnesium calcium carbonate hydrate, magnesium calcium carbonate, andmixtures thereof.
 8. The polyolefin composition according to claim 5,wherein the inorganic filler (II) is an inorganic oxide or salt selectedfrom CaO, TiO₂, Sb₂O₃, ZnO, Fe₂O₃, CaCO₃, BaSO₄ and mixtures thereof. 9.The polyolefin composition according claim 5, wherein the polyolefincomposition has a Shore D hardness lower than 50, an elongation at breakhigher than 200%, and a tensile strength at break equal to or higherthan 10 MPa.
 10. An article comprising a polyolefin compositioncomprising: a polyolefin composition (I), wherein the polyolefincomposition (I) comprises the following fractions: A) from 20 to 40% byweight of a crystalline polymer fraction selected from the groupconsisting of a propylene homopolymer, and a copolymer of propylene withone or more comonomers selected from ethylene and a CH₂═CHRalpha-olefin, where R is a C₂-C₈ alkyl radical, or mixtures thereof,wherein the homopolymer or copolymer containing at least 85% by weightof units derived from propylene, wherein the crystalline fraction has afraction insoluble in xylene at 25° C. of at least 90% by weight; B)from 60 to 80% by weight of an elastomeric fraction comprising acopolymer or blends of copolymers of ethylene with one or morecomonomers selected from propylene and CH₂═CHR alpha-olefins, where R isa C₂-C₈ alkyl radical, and optionally with minor quantities of a diene;said copolymer or blend containing units derived from ethylene in aquantity equal to or less than 40% by weight; wherein the total weightof A and B fractions is 100%, and the fraction soluble in xylene at 25°C. of said polyolefin composition has IVgpc lower than 2.5 dl/g, theratio Mw/Mn of weight average molecular weight (Mw) to number averagemolecular weight (Mn) measured by gel permeation chromatography (GPC)equal to or more than 4, and the ratio Mz/Mw of Z-average molecularweight (Mz) to weight average molecular weight (Mw) measured by gelpermeation chromatography (GPC) equal to or greater than 2.5.
 11. Thearticle of claim 10, wherein the polyolefin composition comprises: 20 to60% by weight of the polyolefin composition (I), and 40 to 80% by weightof an inorganic filler (II) selected from flame-retardant inorganicfillers and inorganic oxides or salts.
 12. The article of claim 10,wherein the article is a sheet or a film.
 13. The article of claim 10,wherein the article is an inner filling, wherein the inner filling isenclosed in an industrial cable or a cable sheathing.